Objective: The objective was to investigate the frequency and type of chromosomal abnormalities and Y chromosome microdeletions in infertile men with azoospermia and oligozoospermia to ensure appropriate genetic counseling before assisted reproduction in Eastern China. Methods: A total of 201 infertile men (148 with azoospermia and 53 with oligozoospermia) were enrolled. Real-time PCR using six Y-specific sequence-tagged sites of the azoospermia factor (AZF) region was performed to screen for microdeletions. Karyotype analyses were performed on peripheral blood lymphocytes with standard G-banding. Results: Out of 201 infertile patients, 22 (10.95%) had Y microdeletions [17/148 (11.49%) men with azoospermia and 5/53 (9.43%) men with oligozoospermia]. The most frequent microdeletions were in the AZFc region, followed by the AZFaþb þ c, AZFbþc, AZFa, and AZFb regions. Chromosomal abnormalities were detected in 18.91% (38/201) of patients, 34 of which were sex chromosome abnormalities (16.92%) and 4 of which were autosomal abnormalities (1.99%). Chromosomal abnormalities were more prevalent in men with azoospermia (22.97%) than in those with oligozoospermia (7.55%). Conclusions: We detected a high incidence of chromosomal abnormalities and Y chromosomal microdeletions in infertile Chinese men with azoospermia and oligozoospermia. These findings suggest the need for genetic testing before the use of assisted reproduction techniques.

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Precision and accuracy estimation is an important index used to reflect the measurement performance and quality of a measurement system. To reveal the significance and connotations of the precision and accuracy estimation index of a close-range photogrammetry system, several common precision and accuracy estimation methods are proposed. They are explained from a theoretical perspective, and the mechanism of the internal coincidence precision estimation and the external coincidence accuracy estimation are deduced, respectively. Through detailed experimental design and testing, the validity and reliability of the proposed precision and accuracy estimation methods are verified, which provides strong evidence for the quality control, optimization and evaluation of the measurement results from a close-range photogrammetry system. At the same time, it has significance for the further development of precision and accuracy estimation analysis of close-range photogrammetry systems.